Question

after six biology tests, ruben has a mean score of 80. what score does ruben need on the next test to raise his average (mean) to 82?

Answer 1

94

Explanation:

The mean score is the sum of the test scores divided by the number of tests.

Let s = sum of the scores of the first 6 tests.

s/6 = 80

s = 80 × 6

s = 480

The sum of the scores of the first 6 tests is 480.

The next test is the 7th test.

Let x = score of the 7th test.

mean score of the first 7 tests = (s + x)/7

(s + x)/7 = 82

(480 + x)/7 = 82

480 + x = 574

x = 94

Answer: 94